Supplementary scan lexical symbol identifier

ABSTRACT

After a curve follower lexical symbol recognition system has completed a character examination and found a conflict to exist, a supplementary scan of the character is initiated only for resolving the conflict. The scan traverses across the character at a horizontal and/or vertical level at which there is an identification number of crossovers for the particular conflict. The number of crossovers solves the conflict.

United States Patent [72] Inventors William W. Hardin 3,263,216 7/1966Andrews 340/1463 Stewartville; 3.303.465 2/1967 Essinger et al. 340/1463Patrick J. Hurley, Rochester; Patrick J. 3,460,091 8/1969 McCarthy etal. 340/1463 Traglh, Rochester, all of, Minn.; Reini J. OTHER REFERENCESBrown Back et al., IBM TECHNICAL DISCLOSURE BUL- lzl] P 6725l8 LETIN,High-Speed Registration For Position Code (22) F'Ied 1967 Scanning,"Vol. 9 No. 11 Apr 1967. pp. 1593- 1595. [451 Greanias et 31., IBMJOURNAL, The Recognition or [73] Asslgnee lmemauonalnusmess MachmesHandwritten Numerals By Contour Analysis, Jan. 1963. pp.

Corporation Armonk,N.Y.

Primary Examiner-Maynard R. Wilbur Assistant Examiner Leo l-l. Boudreau[54] SUPPLEMENTARY SCAN LEXICAL SYMBOL Attorney-Sughrue. Rothwell, Mion,Zinn and MacPeak IDENTIFIER 4 Claims Drawing Figs. ABSTRACT: After acurve follower lexical symbol recogni- [52] US. Cl 340/1463 tion Systemhas completed a character examination and f d lllt- Cl 606] 9/10 aconflict to exist, a supplementary scan of the character is in- [50]Field of Search 340/1463 mated on|y f resolving the conflict The scantraverses References Cited across the character at a horizontal and/0rvertical level at which there is an identification number of crossoversfor the UNITED STATES PATENTS particular conflict. The number ofcrossovers solves the con- 3,l65,7l8 1/1965 Fleisher 340/l46.3 flict.

44 CURVE FOLLOWER CHARACTER RECOGNITION 48 J 50 SYSTEM (PRIOR ARn V 1 3e38 40 g SUPPLEMENTAL CROSSOVER RECOGNITION conrucr LEVEL SCAN COUNTERLOGIC PAIENIEOIIINIsIRI 8585.588

SHEET 1 OF 4 TOP 5 l LH 3 BOT 2 I 44 HH CURVE FOLLOWER CHARACTERRECOGNITION 48 5O sYsIENIPRIORARII I g [36 3s 40 SUPPLEMENTAL CROSSOVERRECOGNITION CONFLICT LEVEL scAN COUNTER LOGIC TOP /24 MATRIX 5E RESOLVEROPPER HOR I i:/- -420v MIDDLE HOR LOWER HOR 5 420h 20 22 :BOTTOM 55INVtNTORS 2 WILLIAM w. HARDIN PATRICK J. HURLEY PATRICK J. TRAGLIA N N IR REINI J. NORMAN IX LEFTT RIEGHT 7X BY 74-4,K/&-@1, M,Z@/ M,m/

vR VRT ATTORNEYS PATENTEB mm 5 I97;

CURVE FOLLOWER CHARACTER RECOGNITION SYSTEM 6-8 CONF END OF 2ND PASS l-8CONF 4-8 CONF 8-9 CONF SHEET 2 [If 4 RESET COULD BE 9 COULD BE 1 COULDBE 8 0-8 CONF 7-9 CONF RESET START SWEEP LEFT I a SWEEP UPPATENTEUJLINISIQH 8585.588

SHEET 3 BF 4 COULD RESET COUNTER 2 A/IOS SUPPLEMENTARY SCAN LEXICALSYMBOL IDENTIFIER BACKGROUND OF THE INVENTION The invention is in thefield of electronic character readers which scan lexical symbols and,from the nature of the symbols, provide indications of the symbolsscanned.

Curve following character recognition systems such as the type describedin U.S. Pat. No. 3,303,465, operate to follow the curve of a character,perform logic feature tests on the curves and combine the feature testresults-in combinatorial logic. The feature tests and some of thecombinatorial logic for recognizing characters 9 are described in detailin Pat.

3,303,465. In the case of a conflict after the recognition sequence iscomplete, the system performs a third pass" on the character. The thirdpass causes the beam to break through the outside contour of thecharacter and curve follow an inside contour. The waveform generated issubjected to third pass" feature tests which are combined in additionalcombinatorial logic to resolve the conflict or to finally decide thatthe character is unrecognizable. Details of parts of the prior artsystem shown generally in 3,303,465 are illustrated in U.S. Pat. Nos.3,248,699 to Essinger et al., 3,297,989 to Atchley et al. and 3,229,100to Greanias.

SUMMARY OF INVENTION The present invention provides a simpler, morereliable system for use in a character recognition system for resolvingconflicts and eliminates the need for the third pass feature tests ofthe prior art. The present invention performs a supplementary scan onthe character which could not be unambiguously identified by therecognition logic. The scan is not a contour scan but is simply avertical and horizontal scan across the character. The numberofcrossovers or hits is counted and used to identify the character. Theposition of the horizontal and vertical scan across the characterdepends upon the type of conflict. For example, for an 8-9 conflict, thebeam is made to scan horizontally across the lower part of thecharacter. If there are two hits" counted, the character is an eight; ifthere is one hit recorded, the character is a nine. In this type ofconflict the vertical scan would not even be necessary to resolve theconflict, but it should be apparent that for other types of conflicts avertical scan alone will resolve the conflict. For a 79 conflict avertical scan along the left side of the character will identify the 7(one hit) or the 9 (two hits).

In the following description and claims unless it appears otherwise, theword conflict" is used broadly to mean that the character wasunrecognizable by the curve follower system. The conflict couldrepresent the coincident recognition of two or more characters, thealmost, but not quite, recognition ofa single character, or even thealmost recognition of two characters. As will be obvious to anyone ofordinary skill in the art, the conflict conditions are generated bylogically combining the feature tests of the curve follower system whichwould apply to the particular conflict.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I shows one type of conflict andthe outer contour seen by the prior art curve follower.

FIG. 2 is a block diagram showing the relationship of the functionalparts of the present invention and the prior art contour scanner.

FIG. 3 is a block diagram of a part of the system logic for generatinginitiating, and other control inputs.

FIG. 4 is a partial schematic illustrating the generation of othercontrol inputs from the matrix resolver of the prior art.

FIG. 5 is a block diagram of the logic which commands the scanner toscan the desired pattern.

FIG. 6 is a block diagram of an example of the recognition logic andcrossover counter for examples of conflicts.

FIG. 7 is a block diagram of logic for generating the conflictindications from conditions generated in the prior art system.

DETAILED DESCRIPTION OF THE DRAWINGS Throughout the detailed descriptionof the drawings one example of a preferred embodiment of the presentinvention will be described. The logic shown will be described inaccordance with conventional positive logic although it is not intendedto be limited to positive logic. It will also be pointed outspecifically how some types of conflicts are resolved and generally howothers are resolved. However, from the description given it will beapparent to anyone having ordinary skill in the art how other possibleconflicts can be resolved by the present invention.

Referring now to FIG. I there is shown one specific type of conflict,referred to herein as the 4-8 conflict. The left solid character is alexical 4, the middle solid character is a lexical 8. For either of thetwo solid characters of the form shown, the recognition system of theprior art (U.S. Pat. No. 3,303,465) will see substantially the sameoutline. The outline is shown by the symbol on the right of the drawing.Thus, the character recognition system, after the second pass, will notknow whether it is examining a four or an eight.

Upon the termination of the second pass in the recognition system and anotification that a conflict has occurred the.

present invention causes the scanner to trace across the character at alevel which will enable resolution of the con flict. The sequence of thescan, referred to herein as the supplementary scan, is illustrated bythe arrows in FIG. 1.

Before describing the supplementary scan, it should be noted that in thecharacter recognition system of the prior art all characters arenormalized after the first pass of the curve follower. Normalization isperformed by a matrix resolver, an example of which is shown in U.S.Pat. No. 3,248,699 to Essinger et al. Normalization effectively removesoverall size as an identifying factor and enables the electronics tosee" all characters as being of the same size. The electronic normalizedmatrix is illustrated best in FIGS. 5A through 8A of U.S. Pat. No.3,303,465 to Essinger et al. and is created by putting the maximum andminimum voltages of the vertical and horizontal beam excursions duringthe first pass onto vertical and horizontal voltage dividers.

For the supplementary scan it is not necessary to use all of the areaidentifying signals from the matrix resolver. It is only necessary toidentify certain levels within the character field. For the specificembodiment described herein it is necessary to identify five horizontallevels, including the top and bottom, and four vertical levels,including the right and left boundaries. The levels are illustrated bythe dash marks associated with the solid line 4 character of FIG. 1. Thehorizontal levels and their identifying symbols are: top (TOP); upperhorizontal (UH); middle horizontal (MI-I); lower horizontal (LI-I); andbottom (BOT). The vertical levels are: right boundary (7X); rightvertical (RV); left vertical (LV); and left boundary (1X).

It will be apparent to anyone having ordinary skill in the art thatvoltages for identifying the levels may be obtained by tapping thevoltage divider of the matrix resolver at convenient points. An exampleis shown in FIG. 4, where the block represents the matrix resolver ofFIG. 2 of U.S. Pat. No. 3,248,699 to Essinger et al.

The only elements shown in detail are the voltage divider 420h and 420V. The voltages in hubs 22 and 20 represent the maximum and minimumexcursions of the first pass scan along the x axis, and the voltages onhubs 24 and 26 represent the maximum and minimum excursions of the firstpass scan along the y axis. The level identifying voltages necessary forthe supplementary scan could be tapped off at points as indicated in thedrawing.

Referring back to FIG. I, the numeral 1 identifies the point at whichthe recognition scan comes to rest after completion of the second pass.The actual position of this point is not important. Upon initiation ofthe supplementary scan logic, the trace is caused to move in thefollowing manner.

1. The trace is moved right and down until it reaches the bottom of thecharacter (BOT) and the right boundary (7X). This is indicated by thearrow between points 1 and 2.

2. Next the trace moves up the 7X boundary until it reaches the selectedlevel. The selected level will be either LH, MH or UH, and is selectedby logic which responds to the particular conflict. For the illustrated4-8 conflict, the LH level is selected. This is illustrated by the arrowbetween points 2 and 3.

3. The trace is then moved horizontally across the character until itreaches the 1X boundary as indicated by the arrow between points 3.and4. During this scan the crossovers from white to black (known as hits)are accumulated in a horizontal counter.

4. The trace is next moved up and to the right. The upward movementstops when TOP is reached and the right movement is stopped at a leveldependent on the type of conflict. The level could be LV, RV or 7X. Thisscan is indicated by the arrow between points 4 and 5.

5. The last movement of the trace in the supplemental scan is verticallydown to the BOT level. This is indicated by the arrow between points 5and 6. During the latter trace the crossovers are counted in a verticalcounter.

The preferred embodiment is arranged so that the horizontal and verticalcrossovers in steps 3 and above are counted for all conflicts, eventhough only one or the other may be necessary to resolve the conflict.For example, in the 4-8 conflict only the horizontal crossovers areneeded to identify the 4 or 8. If there are two crossovers, thecharacter is an eight; if there is one crossover the character is afour.

In FIG. 2 there is shown a functional block diagram of the invention andits relation to the prior art curve follower character recognitionsystem 30. The interconnections to the prior art system are only showngenerally since the specific terminals to which the leads would beconnected would be obvious to anyone of ordinary skill in the art and itwould be superfluous to repeat drawings already known in the prior art.

The conflict identifications at the end of a second pass in system 30are sensed by the supplemental scan unit 32 via leads 40. The particularmanner in which the conflicts are determined by the system 30 forms nopart of the present invention since it is a function of the presentinvention to resolve a conflict once an indication is given and not togenerate the conflict indicating signal. However, for the purpose ofaiding the description of the specific embodiment of the invention thelogic which will respond to the latch and feature test outputs of theprior art to indicate certain conflicts is shown in FIG. 7. The inputsto the gates are from the hardware shown in Pat. 3,303,465.Specifically, the LXX inputs are from the recognition latches of thesame number, and the OXX inputs are the feature tests. Alltriangular-shaped elements are AND functions, all half moon-shapedelements are OR functions, and all boxes with I in the middle are invertfunctions. The logic is self-explanatory to anyone of ordinary skill inthe art and will not be discussed further herein.

Referring back to FIG. 2, in response to the conflict indications thesupplemental scan unit 32 provides vertical and horizontal controllingvoltages to move the trace in a manner described in connection with FIG.I. The horizontal and vertical controlling voltages are applied tosystem 30 via leads 46 and 48 respectively. The supplemental scan unit32 also receives the level voltages via leads 38. The latter voltagesmay be derived from the matrix resolver in the manner described inconnection with FIG. 4.

The crossover counters 34 are controlled by the supplemental scan unit32 via leads 52 to count the video pulses corresponding to crossoversreceived via lead 44. The number of crossovers and the conflictindications are logically combined in recognition logic 36 to resolvethe conflict at the end of the supplemental scan.

A detailed example of the logic for resolving the conflict is shown inFIGS. 3, 5 and 6. In FIG. 3 the conflict indications are divided intofive groups by OR gates 50 through 57. They are grouped according to thelevel across which an identifying scan is to be made. For example, the6-8 and I8 conflicts have identifying numbers of crossovers across theupper horizontal level, therefore the output C is used in subsequentlogic to select the UH level for a horizontal scan. All of the outputsAD are used to selecta level to be traversed by the scan. The latteroutputs are also passed to an OR gate 58, the output thereof indicatingthat a conflict exists.

At the end of the second pass around the character by the system 30, atermination output is ANDed with the conflict indication in gate 62, theoutput therefrom triggering single shot 64 to provide a positive RESEToutput pulse. The RESET output pulse is applied to a single shot 70which responds to the trailing edge of the RESET output pulse togenerate a START pulse.

The START, RESET and AD outputs are used to control the logic of FIG. 5which operates to select the levels of the character to be scanned.There are five latches shown in FIG. 5. The SWEEP RIGHT latch 80, SWEEPDOWN latch 84, SWEEP LEFT latch 86 and SWEEP UP latch 88 control theelectron beam of the scanner of the prior art system to move in theindicated direction. Controlling a cathode ray beam in any direction inaccordance with the command outputs of the latches will be obvious toanyone having ordinary skill in the art.

The fifth latch, labeled OK VERT latch 82 provides a condition outputwhich is used as a gating input for the vertical counter as shown inFIG. 6. All of the latches 82-86 include an AND gate and an OR gate. Alatch is SET by a positive input to the OR gate and is RESET by anegative input to the AND gate.

The logic of FIG. 5 also includes nine discriminators D10- D26, one foreach level voltage picked off the voltage dividers of FIG. 4. Eachdiscriminator has a level voltage applied to one input and either avertical or horizontal voltage applied to the second input. The verticaland horizontal voltages are at all times proportional to the verticaland horizontal position of the scan, and, as is well known in the art,may be tapped off the input to the vertical and horizontal deflectionplates or coils. The purpose of each discriminator is to provideanelectronic indication when the scan reaches the level correspond ingto the voltage level input to the discriminator.

Although many kinds of discriminators can be used in the logic of theinvention, the ones described in the specific embodiment herein operateto provide positive and negative outputs on the opposite outputterminals for one relative amplitude condition of the inputs, and toprovide the reverse outputs for an opposite relative amplitude conditionof the inputs. Specifically, when the voltage on the minus inputterminal is below the voltage on the positive input terminal, thevoltages on the output terminals have the polarity indicated by thesigns. Otherwise, the upper output terminal will be negative and thelower output terminal will be positive.

The inputs AC, from FIG. 3, are ANDed with the outputs from the LH, MHand UI-! discriminators to select the level for a horizontal scan. Theinputs D and E are ANDed with the outputs from the LV and RVdiscriminators to select the level for a vertical scan.

A complete supplementary scan is accomplished as follows:

When a RESET is generated by the single shot 64 (FIG. 3), the RESETinput to latches --88 becomes negative thereby resetting all latches.When RESET becomes positive a START pulse is generated and applied toSWEEP RIGHT latch 80 and SWEEP DOWN latch 84, setting those latches andcausing the scan to move from the start position toward the right anddown.

When the scan reaches the 7X boundary the upper output of D10 becomesnegative and resets latch 80 stopping the movement to the right. Whenthe scan reaches the BOT level the lower output of D12 goes negativeresetting latch 84 to stop the downward movement of the scan. The firststep of the supplemental scan ends at the 7X and BOT boundaries. Underthese conditions the lower output of D10 is positive and the upperoutput of D12 is positive. The latter outputs are ANDed and applied tothe OR gate oflatch 88 to start a scan in the up direction.

The up scan, indicated by the arrow between points 2 and 3 in FIG. '1,is stopped at level LH, MH or UH depending upon which of the inputs Athrough C is selected. For the 4-8 conflict, input A is positive andthus, the LH level is selected. When the scan reaches the LH level, thelower output of D14 becomes positive and is ANDed with input A totrigger single shot 90 to provide a relatively short positive outputpulse. The positive output pulse may be on the order of a fewnanoseconds. The positive pulse is inverted by invertor 92 therebycausing the SWEEP UP latch to be reset. At the same time the positivepulse from single shot 90 sets the SWEEP LEFT latch 86 causing the scanto proceed across the character at the selected level. The purposeofproviding a single shot 90 is to allow the SWEEP UP latch 88 to be setduring a later step even though the scan is above the selectedhorizontal level.

When the scan reaches the 1X boundary, the lower output of D resetslatch 86 and the upper output of D20 sets latches 80, 88 and 82. Latches80 and 88 cause scanning to proceed to the right and upward, and latch82 provides conditioning inputs to AND gates 94 through 98.

When the scan reaches the TOP level, the upper output of D26 resetsSWEEP UP latch 88 and the lower output provides one positive input toAND gate 100. The movement to the right is stopped at the LV level if Dis positive, at the RV level if E is positive or at the 7X level ifneither D nor E is positive. lfD is positive, when the scan reacheslevel LV a positive output from AND gate 96 is inverted by invertor 102to reset SWEEP RIGHT latch 80. If E is positive a similar operationtakes place. If neither is positive, when the scan reaches the 7X level,the upper output of D10 resets the SWEEP RIGHT latch 80. In all threecases, a positive input will appear at OR gate 104 thereby providing asecond positive input to AND gate 100. The output of AND gate 100 setsthe SWEEP DOWN latch 84 thereby starting the vertical scan during whichcrossovers are counted.

When the scan reaches the BOT level, the lower output of D12 resetslatches 84 and 82 stopping the downward scan and removing the positiveconditioning signal OK VERT. As OK VERT goes negative a single shot 106responsive to the negative going input provides a read out output pulseR0 of predetermined duration. The RO pulse enables the read outcircuitry. Although not shown in the drawing, the RO pulse may beinverted and applied to the AND gates of all latches 80-88 to insurethat all latches are reset following the vertical scan.

The counters and associated logic are shown in FIG. 6. The logic isself-explanatory and thus only the resolution of the 4- 8 conflict willbe described in detail. The output latches are set in accordance withthe character identified. For example if an eight is identified, latchL8 is set, ifa four is identified latch L4 is set. When there is noidentification at the end of a supplementary scan, latch LNI is set. Thehorizontal counter 112, vertical counter 114 and all latches are resetby the RESET pulse input.

The video pulses, corresponding to crossovers in the scans, aregenerated by the prior art recognition system and applied to AND gates108 and 110 via lead 109. During the scan across the character at theselected horizontal level, the SWEEP LEFT input from latch 86 (FIG. 5)energizes AND gate 108 to pass the video pulses to horizontal counter112. Thus, the horizontal counter registers the number of crossoversduring the horizontal scan. During the vertical scan across thecharacter at the selected level, latches 84 and 82 (FIG. 5) are setthereby providing energization of AND gate 110. Thus, vertical counter114 registers the crossovers during the vertical scan.

For the 48 conflict of FIG. 1, the vertical count is unimportant. If thecharacter is an eight, the counter 112 will register a count of two. Thetwo count output of counter 112 is ANDed with the 4-8 conflict line ingate 116, whose output is applied through OR gate to AND gate 122. Whenthe RO pulse occurs, an output from AND gate 122 sets latch L8indicating that the character is an eight.

If the character is a four, counter 112 provides an output at the onecount terminal which is ANDed in AND gate 118 with the 4-8 conflictline. When the RO pulse occurs the output from gate 118 passes throughgate 124 to set latch L4 thereby indicating that the character is afour.

In the above description of the invention it was pointed out that thetype of conflict selects the levels to be scanned for resolution of theconflict. However, it will be noted from FIG. 3 that neither A, B nor Cis selected by a 0-8, 7-9, or could be 8 conflict and therefore therewill be no selection of a horizontal level. Since the horizontal levelis unimportant for the latter conflicts, any one of the outputs A, B orC can be selected. This is accomplished by tying the latter conflictlines to any one of the inputs to OR gates 50, 52 or 54.

While the invention has been particularly shown and described withreference to a preferred embodiment thereof, it will be understood bythose skilled in the art that various changes in form and details may bemade therein without departing from the spirit and scope of theinvention.

What we claim is:

1. Apparatus for resolving a conflict in the identification of a lexicalcharacter comprising;

means responsive to each of a plurality of conflict identificationsignals for scanning the character in a different one of a plurality ofdifferent scan patterns for each conflict signal, each scan patterneffecting a scan across a portion of the character which has a uniquedetectable quality for each possible solution to said conflict, saidunique detectable quality being number of crossovers, and

means responsive to said conflict identification and said uniquedetectable quality for providing a solution to the conflict,

wherein said means for scanning comprises,

means for electrically dividing the field of said characters into pluralseparate levels,

means responsive to said conflict identification for selecting a levelin which an identifying number of crossover points exists for theconflict, and

means responsive to said selected level for scanning across saidcharacter at said selected level.

2. Apparatus as claimed in claim 1 wherein said electrically dividingmeans divides said field into groups of substantially orthogonal levels.

3. Apparatus for resolving a conflict in the identification of a lexicalcharacter comprising;

means responsive to each of a plurality of conflict identificationsignals for scanning the character in a different one of a plurality ofdifferent scan patterns for each conflict signal, each scan patterneffecting a scan across a portion of the character which has a uniquedetectable quality for each possible solution to said conflict, saidunique detectable quality being number of crossovers, and

means responsive to said conflict identification and said uniquedetectable quality for providing a solution to the conflict,

wherein said means for scanning comprises;

a. first logic means responsive to said conflict for selecting one of agroup of conditioning signals each representing a different level of thefield of said character, the signal selected representing a level acrosswhich are a different number of crossovers for each possible solution tosaid conflict,

b. means for generating electrical level signals corresponding to saiddifferent levels for every character being examined,

means responsive to any conflict identification for causing apredetermined first scan in the field of said character and forproviding voltage'indications of the position of said scan,

. means responsive to said position indication voltages,

4. Apparatus for resolving a conflict in the identification of a lexicalcharacter comprising;

means responsive to each of a plurality of conflict identificationsignals for scanning said character in a different one of a plurality ofdifferent scan patterns for each conflict signal, each scan patterneffecting a scan across a portion of the character which has a uniquedetectable quality for each possible solution to said conflict, saidunique detectable quality being number of crossovers, and

means responsive to said conflict identification and said uniquedetectable quality for providing a solution to the conflict,

wherein said means for scanning comprises,

ages and normalized vertical level voltages corresponding to varioushorizontal and vertical levels of said character,

a plurality of vertical discriminator means, each responsive to onevertical level voltage and the voltage corresponding to the verticalposition of said scan for providing an indication when said scan reachessaid one vertical level,

. a plurality of horizontal discriminator means, each responsive to onehorizontal level voltage and the voltage corresponding to the horizontalposition of said scan for providing an indication when said scan reachessaid one horizontal level,

. means responsive to the presence of a conflict for causing saidcontrol voltage generating means to move said scan in a predeterminedpattern,

means responsive to said conflict identification for selecting onevertical and one horizontal discriminator,

. means responsive to said horizontal discriminator indication that saidscan has reached said one horizontal level for causing said controlvoltage generating means to move said scan across said character at saidone horizontal level, and

. means responsive to said vertical discriminator indication that saidscan has reached said one vertical level for causing said controlvoltage generating means to move said scan across said character at saidone vertical level.

1. Apparatus for resolving a conflict in the identification of a lexicalcharacter comprising; means responsive to each of a plurality ofconflict identification signals for scanning the character in adifferent one of a plurality of different scan patterns for eachconflict signal, each scan pattern effecting a scan across a portion ofthe character which has a unique detectable quality for each possiblesolution to said conflict, said unique detectable quality being numberof crossovers, and means responsive to said conflict identification andsaid unique detectable quality for providing a solution to the conflict,wherein said means for scanning comprises, means for electricallydividing the field of said characters into plural separate levels, meansresponsive to said conflict identification for selecting a level inwhich an identifying number of crossover points exists for the conflict,and means responsive to said selected level for scanning across saidcharacter at said selected level.
 2. Apparatus as claimed in claim 1wherein said electrically dividing means divides said field into groupsof substantially orthogonal levels.
 3. Apparatus for resolving aconflict in the identification of a lexical character comprising; meansresponsive to each of a plurality of conflict identification signals forscanning the character in a different one of a plurality of differentscan patterns for each conflict signal, each scan pattern effecting ascan across a portion of the character which has a unique detectablequality for each possible solution to said conflict, said uniquedetectable quality being number of crossovers, and means responsive tosaid conflict identification and said unique detectable quality forproviding a solution to the conflict, wherein said means for scanningcomprises; a. first logic means responsive to said conflict forselecting one of a group of conditioning signals each representing adifferent level of the field of said character, the signal selectedrepresenting a level across which are a different number of crossoversfor each possible solution to said conflict, b. means for generatingelectrical level signals corresponding to said different levels forevery character being examined, c. means responsive to any conflictidentification for causing a predetermined first scan in the field ofsaid character and for providing voltage indications of the position ofsaid scan, d. means responsive to said position indication voltages,said electrical level signals, and said selected conditioning signalrepresenting a selected level for terminating said first scan and forcausing a second scan across said character at said selected level whensaid scan reaches said selected level, and e. means for counting thenumber of crossovers encountered by said second scan.
 4. Apparatus forresolving a conflict in the identification of a lexical charactercomprising; means responsive to each of a plurality of conflictidentification signals for scanning said character in a different one ofa plurality of different scan patterns for each conflict signal, eachscan pattern effecting a scan across a portion of the character whichhas a unique detectable quality for each possible solution to saidconflict, said unique detectable quality being number of crossovers, andmeans responsive to said conflict identification and said uniquedetectable quality for providing a solution to the conflict, whereinsaid means for scanning comprises, a. means for generating horizontaland vertical control voltages for controlling the position of a scancharacter, b. means for generating normalized horizontal level voltagesand normalized vertical level voltages corresponding to varioushorizontal and vertical levels of said character, c. a plurality ofvertical discriminator means, each responsive to one vertical levelvoltage and the voltAge corresponding to the vertical position of saidscan for providing an indication when said scan reaches said onevertical level, d. a plurality of horizontal discriminator means, eachresponsive to one horizontal level voltage and the voltage correspondingto the horizontal position of said scan for providing an indication whensaid scan reaches said one horizontal level, e. means responsive to thepresence of a conflict for causing said control voltage generating meansto move said scan in a predetermined pattern, f. means responsive tosaid conflict identification for selecting one vertical and onehorizontal discriminator, g. means responsive to said horizontaldiscriminator indication that said scan has reached said one horizontallevel for causing said control voltage generating means to move saidscan across said character at said one horizontal level, and h. meansresponsive to said vertical discriminator indication that said scan hasreached said one vertical level for causing said control voltagegenerating means to move said scan across said character at said onevertical level.